1. Technical Field
The present invention generally relates to display correction and, more specifically, to correcting the displayed color by reducing its dependency on various variables, such as temperature.
2. Background Discussion
Many computing devices use an electronic display to present information to a user. Such displays may be, for example, liquid crystal displays (“LCDs”), cathode ray tubes (“CRTs”), organic light emitting diode displays (“OLED displays”) and so on. Most such displays can show color images. However, the color response of a display may change as the display operates.
In particular, the display's white point may shift along a blackbody curve as the physical temperature of the display reaches a steady operating temperature. For example, when a display is turned on, the display may be cold and the temperature of the display may increase as the display warms up over time. The changing temperature of the display may cause the display colors to shift. For example, some displays depict white as somewhat yellowish when initially powered on and cold. As the display warms, the white point of the display shifts toward a more neutral white, such as defined by the standard illuminant, D65. The same is true for any colors shown on the display; they too shift within a color space as the temperature of the display increases. This is true even if, for example, the display only outputs grayscale colors (e.g., is a black and white display). Similarly, other parameters of the display may shift as a function of temperature such as luminance, black level, contrast, or electro-optical transfer function, which may be referred to as the “native gamma” of the display. This set of parameters may be referred to as the color profile of the display.
The shift in the color profile due to temperature increase of the display generally causes each pixel of the display to change color until a stable operating temperature is achieved, at which point the pixel colors are likewise stable. That is, although a pixel may be instructed to display the same color at an initial temperature and a stable operating temperature, the actual color displayed, as objectively measured by its chrominance and luminance, may vary. It should be noted that, in many electronic systems, individual pixels of a display receive a red, greed and blue value that together define the color to be created by the pixel. These red, green and blue values are referred to herein in the aggregate as an “RGB value,” as understood to those of ordinary skill in the art.
Thus, a method of adjusting the display colors over a range of display temperatures is desirable. Accordingly, there is a need in the art for an improved method of providing consistent display colors over a range of parameters including temperature.